ATLANTA (AP) — Coach Brent Thompson was working as The Citadel's offensive coordinator when the school upset South Carolina four years ago.

Now that he's got a signature win of his own, Thompson has a big building block for his team.

"This is what we needed as a program, what I needed to get this program going in the right direction for the rest of the season," Thompson said, "because we've got our whole conference schedule to play after this."

Jacob Godek kicked a 37-yard field goal in overtime, quarterback Brandon Rainey ran for one touchdown and passed for another, and FCS The Citadel stunned Georgia Tech with a 27-24 upset victory on Saturday.

Georgia Tech's defense allowed 320 yards rushing against the triple-option, a scheme it faced in practice the last 11 years under former coach Paul Johnson, but the Yellow Jackets (1-2) still figured to have an enough talent to overcome The Citadel.

Instead, the Bulldogs (1-2) never trailed despite having lost FCS games at home to Towson and on the road to Elon. Beating the Jackets gave The Citadel its first win over an FBS opponent since 2015 against South Carolina. Before that, the Bulldogs had not won against the higher classification since knocking off Arkansas and Army in 1992.

"We'll celebrate this one for 24 hours and get back to work tomorrow," Rainey said. "You can't really hang onto wins. It'll set you back, so we're on to the next one."

It was the Jackets' first loss to an FCS or a Division I-AA opponent since Furman in 1983 and their first in 11 games against The Citadel.

Momentum turned in the third quarter when Rainey broke a 14-all tie with a 22-yard TD run, and strong safety Sean-Thomas Faulkner stopped Georgia Tech's Jordan Mason for no gain on the ensuing drive.

Rainey limped off the field early in the fourth and was replaced by Brian Murdaugh the rest of the way. Godek split the uprights to make it 24-21 with 1:51 to go. Brenton King sent the game to overtime with a 34-yard field goal at the end of regulation, but he missed wide left from 46 yards to end the first possession of the extra period.

New Georgia Tech coach Geoff Collins has struggled to find a formula for his up-tempo, pro-style offense, rotating quarterbacks Lucas Johnson and Tobias Oliver to mixed results in a blowout loss at No. 1 Clemson and a narrow home win over South Florida.

The end of regulation was a mess. Collins called timeout just before Oliver took a snap and ran for a 17-yard TD. With the score nullified and time for just one play, Collins had to send out King instead of going for the win.

He appeared slightly agitated with reporters when asked about next week's starting quarterback.

"So again, we don't talk like that," Collins said. "If you noticed out there today, there were probably six safeties that played in the college football game. I don't see people asking me who is going to be the starting safety moving forward. We don't think in those terms. The people can help us play really well — they're going to play."

Georgia Tech tied it at 14-all when Johnson completed a 33-yard touchdown pass and a conversion pass to Jalen Camp. Jordan Mason ran for 25 yards to make it 21-all with 7:29 remaining.

The Citadel got on the board in the first when Raleigh Webb ran past the coverage for an easy 30-yard touchdown catch. It was Rainey's only completion in four attempts.

Georgia Tech scored on its third drive when Oliver pitched to Mason for a 4-yard score. The Jackets quickly fizzled when Wesley Wells, a sophomore, missed his first career extra-point attempt.

The Citadel used up most of the final 6 minutes of the second quarter with a 13-play, 67-yard drive that ended with Dante Smith's 12-yard touchdown run and a 14-6 halftime lead.

King replaced Wells in the fourth, kicking the PAT that tied it at 21-all.

INJURIES

Rainey had to be helped off the field as he limped toward the sideline with a knee injury. He stood and watched the rest of the game. ... Georgia Tech left tackle Jahaziel Lee was carted off the field with a left leg injury after getting cut-blocked early in the fourth. ... Bulldogs linebacker Phil Davis limped off the field after getting hurt on Mason's TD run. ... The Citadel B-back Clay Harris walked slowly off the field midway through the fourth.

THE TAKEAWAY

The Citadel: The Bulldogs can enjoy this one for a long time, a victory that gives Thompson a new recruiting and fundraising tool after undergoing consecutive 5-6 seasons.

Georgia Tech: The Jackets have enough problems without being undisciplined. They were unruly on the fourth defensive series as cornerback Kaleb Oliver was flagged for taunting and defensive tackle Chris Martin was penalized for unsportsmanlike conduct to nullify linebacker David Curry's 4-yard stop on Rainey's third-down scramble. After Rainey threw an interception, T.K. Chimedza was called for unsportsmanlike conduct.